add support for Explicit Resource Management to mocked functions

babel.config.js

@@ -38,6 +38,7 @@ module.exports = {
   plugins: [
     ['@babel/plugin-transform-modules-commonjs', {allowTopLevelThis: true}],
     require.resolve('./scripts/babel-plugin-jest-require-outside-vm'),
+    '@babel/plugin-proposal-explicit-resource-management',
   ],
   presets: [
     [

package.json

@@ -4,6 +4,7 @@
   "version": "0.0.0",
   "devDependencies": {
     "@babel/core": "^7.11.6",
+    "@babel/plugin-proposal-explicit-resource-management": "^7.23.9",
     "@babel/plugin-transform-modules-commonjs": "^7.1.0",
     "@babel/preset-env": "^7.1.0",
     "@babel/preset-react": "^7.12.1",
@@ -81,7 +82,7 @@
     "tempy": "^1.0.0",
     "ts-node": "^10.5.0",
     "tstyche": "^1.0.0-beta.9",
-    "typescript": "^5.0.4",
+    "typescript": "^5.2.2",
     "webpack": "^5.68.0",
     "webpack-node-externals": "^3.0.0",
     "which": "^4.0.0"

packages/jest-mock/src/__tests__/index.test.ts

@@ -12,6 +12,14 @@ import * as util from 'util';
 import {type Context, createContext, runInContext, runInNewContext} from 'vm';
 import {ModuleMocker, fn, mocked, spyOn} from '../';
 
+if (!Symbol.dispose) {
+  Object.defineProperty(Symbol, 'dispose', {
+    get() {
+      return Symbol.for('nodejs.dispose');
+    },
+  });
+}
+
 describe('moduleMocker', () => {
   let moduleMocker: ModuleMocker;
   let mockContext: Context;
@@ -2432,3 +2440,26 @@ test('`fn` and `spyOn` do not throw', () => {
     spyOn({apple: () => {}}, 'apple');
   }).not.toThrow();
 });
+
+describe('Explicit Resource Management', () => {
+  it('jest.fn state should be restored with the `using` keyword', () => {
+    const mock = jest.fn();
+    {
+      using inScope = mock.mockReturnValue(2);
+      expect(inScope()).toBe(2);
+      expect(mock()).toBe(2);
+    }
+    expect(mock()).not.toBe(2);
+  });
+
+  it('should be restored with the `using` keyword', () => {
+    {
+      using mockedLog = jest.spyOn(console, 'log');
+      expect(jest.isMockFunction(console.log)).toBeTruthy();
+
+      console.log('test');
+      expect(mockedLog).toHaveBeenCalled();
+    }
+    expect(jest.isMockFunction(console.log)).toBeFalsy();
+  });
+});

packages/jest-mock/src/index.ts

@@ -5,6 +5,8 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+/// <reference lib="ESNext.Disposable" />
+
 /* eslint-disable local/ban-types-eventually, local/prefer-rest-params-eventually */
 
 import {isPromise} from 'jest-util';
@@ -131,7 +133,8 @@ type ResolveType<T extends FunctionLike> =
 type RejectType<T extends FunctionLike> =
   ReturnType<T> extends PromiseLike<any> ? unknown : never;
 
-export interface MockInstance<T extends FunctionLike = UnknownFunction> {
+export interface MockInstance<T extends FunctionLike = UnknownFunction>
+  extends Disposable {
   _isMockFunction: true;
   _protoImpl: Function;
   getMockImplementation(): T | undefined;
@@ -797,6 +800,9 @@ export class ModuleMocker {
       };
 
       f.withImplementation = withImplementation.bind(this);
+      if (Symbol.dispose) {
+        f[Symbol.dispose] = f.mockRestore;
+      }
 
       function withImplementation(fn: T, callback: () => void): void;
       function withImplementation(

tsconfig.json

@@ -8,6 +8,7 @@
     "declaration": true,
     "emitDeclarationOnly": true,
     "stripInternal": true,
+    "lib": ["es2021", "ESNext.Disposable"],
 
     "strict": true,
 

yarn.lock

@@ -690,6 +690,18 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@babel/plugin-proposal-explicit-resource-management@npm:^7.23.9":
+  version: 7.23.9
+  resolution: "@babel/plugin-proposal-explicit-resource-management@npm:7.23.9"
+  dependencies:
+    "@babel/helper-plugin-utils": ^7.22.5
+    "@babel/plugin-syntax-explicit-resource-management": ^7.23.3
+  peerDependencies:
+    "@babel/core": ^7.0.0-0
+  checksum: d7a37ea28178e251fe289895cf4a37fee47195122a3e172eb088be9b0a55d16d2b2ac3cd6569e9f94c9f9a7744a812f3eba50ec64e3d8f7a48a4e2b0f2caa959
+  languageName: node
+  linkType: hard
+
 "@babel/plugin-proposal-export-default-from@npm:^7.0.0":
   version: 7.23.3
   resolution: "@babel/plugin-proposal-export-default-from@npm:7.23.3"
@@ -841,6 +853,17 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@babel/plugin-syntax-explicit-resource-management@npm:^7.23.3":
+  version: 7.23.3
+  resolution: "@babel/plugin-syntax-explicit-resource-management@npm:7.23.3"
+  dependencies:
+    "@babel/helper-plugin-utils": ^7.22.5
+  peerDependencies:
+    "@babel/core": ^7.0.0-0
+  checksum: 60306808e4680b180a2945d13d4edc7aba91bbd43b300271b89ebd3d3d0bc60f97c6eb7eaa7b9e2f7b61bb0111c24469846f636766517da5385351957c264eb9
+  languageName: node
+  linkType: hard
+
 "@babel/plugin-syntax-export-default-from@npm:^7.0.0, @babel/plugin-syntax-export-default-from@npm:^7.23.3":
   version: 7.23.3
   resolution: "@babel/plugin-syntax-export-default-from@npm:7.23.3"
@@ -3000,6 +3023,7 @@ __metadata:
   resolution: "@jest/monorepo@workspace:."
   dependencies:
     "@babel/core": ^7.11.6
+    "@babel/plugin-proposal-explicit-resource-management": ^7.23.9
     "@babel/plugin-transform-modules-commonjs": ^7.1.0
     "@babel/preset-env": ^7.1.0
     "@babel/preset-react": ^7.12.1
@@ -3077,7 +3101,7 @@ __metadata:
     tempy: ^1.0.0
     ts-node: ^10.5.0
     tstyche: ^1.0.0-beta.9
-    typescript: ^5.0.4
+    typescript: ^5.2.2
     webpack: ^5.68.0
     webpack-node-externals: ^3.0.0
     which: ^4.0.0
@@ -20334,7 +20358,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"typescript@npm:5.3.3, typescript@npm:^5.0.4":
+"typescript@npm:5.3.3, typescript@npm:^5.0.4, typescript@npm:^5.2.2":
   version: 5.3.3
   resolution: "typescript@npm:5.3.3"
   bin:
@@ -20344,7 +20368,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"typescript@patch:typescript@5.3.3#~builtin<compat/typescript>, typescript@patch:typescript@^5.0.4#~builtin<compat/typescript>":
+"typescript@patch:typescript@5.3.3#~builtin<compat/typescript>, typescript@patch:typescript@^5.0.4#~builtin<compat/typescript>, typescript@patch:typescript@^5.2.2#~builtin<compat/typescript>":
   version: 5.3.3
   resolution: "typescript@patch:typescript@npm%3A5.3.3#~builtin<compat/typescript>::version=5.3.3&hash=e012d7"
   bin: